Trailer cover system

ABSTRACT

A rail is disclosed for a top of a wall of a trailer. The rail comprises a body adapted to engage the top of the wall. The body has a concave surface adapted to receive a cover reel.

TECHNICAL FIELD

This invention relates to covers for truck trailers, and moreparticularly to a trailer cover system.

BACKGROUND ART

Many truck trailers, particularly those hauling loose loads such as sandand gravel, need a cover to prevent the wind from blowing load particlesoff the load bed. Various apparatus have been devised for covering atrailer load. Some such apparatus include a motor for selectivelywinding a flexible cover. An effective cover should be one which iseasily operated by the truck driver so as to selectively cover anduncover the load from the convenient location of the truck cab. My U.S.Pat. No. 5,031,955, the disclosure of which is hereby incorporated byreference, provides a truck cover which may be conveniently motoroperated from the cab of a truck to extend the cover from a windingassembly proximate the front of the truck bed and toward the rear of thetruck bed.

A need also exists for systems that cover the trailer from side to side.For instance, U.S. Pat. No. 5,328,228 shows a cover for truck bed andcargo. Similarly, U.S. Pat. No. 5,924,758 shows a roll assist mechanismfor tarp systems. My U.S. Pat. Nos. 6,206,449 and 6,527,331, thedisclosures of which are also hereby incorporated by reference, show aside-to-side truck cover system including a pair of arms, each of whichincludes a base and an extension.

DISCLOSURE OF INVENTION

One aspect of the present invention is a rail for a top of a wall of atrailer. The rail comprises a body adapted to engage the top of thewall. The body has a concave surface adapted to receive a cover reel.

Accordingly, an object of this invention is to provide an apparatus ofthe type described above for use in covering a trailer.

Another object of this invention is to provide an apparatus of the typedescribed above for use in covering the trailer from side to side.

Still another object of this invention is to provide an apparatus of thetype described above for use in a system that provides selective,powered control over covering and uncovering the trailer.

Still another object of this invention is to provide an apparatus of thetype described above that utilizes a relatively reduced number of smallcomponents.

Still another object of this invention is to provide an apparatus of thetype described above that minimizes damage done to the apparatus duringloading operations.

These and other objects, features, and advantages of the presentinvention are readily apparent from the following detailed descriptionof the best mode for carrying out the invention when taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a front schematic view of a trailer including an apparatusaccording to the present invention for covering the trailer;

FIG. 2 is a rear schematic view of the trailer shown in FIG. 1;

FIG. 3 is an enlarged view of a top rail shown in the portion of FIG. 2designated “3”;

FIG. 4 is a perspective view of the top rail;

FIG. 5 is a cross-sectional view of interlocking sections of oneembodiment of a wall of the trailer;

FIG. 6 is a cross-sectional view of the wall sections joined together;and

FIG. 7 is a perspective view of a cover return unit.

BEST MODE FOR CARRYING OUT THE INVENTION

With reference to the drawings, the preferred embodiments of the presentinvention will be described. FIGS. 1 and 2 show an arm assembly 10 for aflexible tarp or cover 12 of a truck trailer 13. The arm assembly 10comprises a base 14 and an extension 18. The base 14 is preferablymounted to the trailer at a base plate 20 proximate the top of the front22 of the trailer. While the base plate 20 is shown in the drawingscentered and closer to the top of the trailer 13, it should beappreciated that the base plate may be mounted at a variety oflocations.

The base plate 20 includes at least one spiral torsion spring.Preferably, one end of each of the springs engages a groove formed inthe surface of and extending a substantial portion of the length of acenter shaft, while the other ends of the springs cooperate with alocator pin. Further details of this arrangement are taught by U.S. Pat.No. 5,887,937, which is hereby incorporated by reference. In this way,the base 14 is normally biased clockwise as shown in FIG. 1 across atleast a portion of the front 22 of the trailer from a mostly or fullyuncovered, stowed position, through intermediate positions (only one ofwhich is shown) and toward a deployed position.

The extension 18 is pivotally connected at one of its ends to the base14 by a hinge or knuckle 28. Preferably, a knuckle shaft is welded orotherwise fixed to one of a pair of plates extending from an upper endof the base 14. The knuckle shaft extends through the lower end of theextension 18 such that the knuckle shaft is rotatable with respect tothe extension. One end of each of a plurality of spiral torsion springspreferably engages an axial groove formed in the knuckle shaft. Theother ends of the springs cooperate with a knuckle locator pin. Furtherdetails of this arrangement are taught by U.S. Pat. No. 5,944,374, whichis hereby incorporated by reference.

In this way, the extension 18 is also normally biased clockwise as shownin FIG. 1. Rotation of the extension 18 in both directions may belimited by one or more stops which are preferably in the form of plates29. The plates 29 are welded or otherwise attached to the knuckle 28,and extend inwardly therefrom to engage the extension and preventoverrotation. Another stop may be welded or otherwise attached to thefront 22 of the trailer to limit the pivotal movement of the base 14, astaught by U.S. patent application Ser. No. 09/957,202 filed Sep. 20,2001, the disclosure of which is hereby incorporated by reference.

A motor 30 is mounted on the distal end of the extension 18. A rotatablereel 32 extends from the motor 30, and is operatively connected to oneend of the cover 12 so as to function as a take-up spool. The other endof the cover 12 is clamped, riveted, or otherwise fixed at one or morepoints along a line below the top of one side 34 of the trailer, such asat one or more openings 36 along a top rail 38. As shown in FIGS. 3 and4, the top rail 38 includes one or more metal or plastic pieces, such asextruded or pultruded aluminum or composite fiberglass polymer. The toprail 38, and an opposite top rail 60, include generally depending legs39 and 40 that are adapted to be mounted over the top of the trailerwall 34 or the opposite trailer wall 41. The legs 39 and 40 may be fixedto the trailer walls in any conventional manner, such as by welding,riveting or bolting. The trailer may also be provided with front andrear end caps, which are not shown, in order to provide a uniform wallheight around the perimeter of the trailer, if the front and rear wallsof the trailer are not already high enough.

The top rails 38 and 60 also each include a major interior surface 42, amajor exterior surface 44, and one or more ribs 46, 48, 50, 52 and 54extending from one or both of the surfaces 42 and 44. In a preferredembodiment shown in the figures, the ribs 46, 48, 50 and 52 all meet ata reinforced section 55 proximate the exterior surface 44. A lockingchannel portion 56 of the exterior surface 44 is concave, in order toaccommodate the stowed tarp spool 32 as shown in FIGS. 1 and 2. Theconcave portion 56 of the top rail 38 includes the opening 36, intowhich the stationary end of the tarp 12 may be anchored in any wellknown fashion. In a preferred embodiment, the tarp 12 is attached to thetop rail 38 by sliding a tube 57 through a pocket in the stationary endof the tarp, and then sliding the stationary end of the tarp and thetube through a void 58 in the top rail with the tarp extending throughthe opening 36. The top rail 60, of course, does not require an openingsimilar to the opening 36.

For either of the top rails 38 or 60, the exterior surface 44 preferablyincludes a rounded lip 62 that extends to a point at or below theuppermost extent of the concave surface 56. In the fully uncoveredposition, the cover 12 is wound on the reel 32 until the reel residesgenerally proximate the concave surface 56. In this position, thetrailer may dump rearwardly or in either the clockwise orcounterclockwise direction without interference from the retractedcover.

The motor 30 is preferably provided with a brake which allows, amongother things, for the apparatus 10 to remain in the stowed position. Thelip 62 facilitates retention of the reel 32 in the stowed position. Whenthe brake is released, the base 14 swings toward the driver's side 41 ofthe trailer, and the springs of the knuckle 28 also bias the extension18 clockwise as shown in FIG. 1 toward the side 41 of the trailer so asto hold the cover 12 in tension. The motor 30 may be powered, fromwithin or without the cab of the truck, to facilitate this operation.Further details of one embodiment of the motor are taught by U.S. Pat.No. 5,829,819, which is hereby incorporated by reference. In this way,the cover 12 is pulled off of the reel 32 and extended over the trailer.The motor 30 can be reversed to drive the reel 32 and retract the cover12 against the tension force of the springs to uncover the load bed.

The top rail 60 is provided with a profile generally similar to theprofile of the top rail 38 so that the motor 30 drives the reel 32within the concave portion of the top rail 60, where the lip of the toprail 60 and the motor braking function may be used to hold the cover 12in the deployed position. The top rails 38 and 60 thus allow the tarpreel 32 to reside close to the sides of the trailer in both the openedand closed positions. Because the tarp reel does not rest on the top ofthe trailer when the tarp is opened or closed, the overall height of thetrailer and the possibility of a loader causing harm to the tarpassembly are reduced.

Any rotation of the base 14 less than about 250 degrees is contemplated,and in a preferred embodiment the base sweeps out an arc of about 120degrees. Any rotation of the extension 18 relative to the base 14 isalso contemplated, and in a preferred embodiment the extension rotates atotal of about 250 degrees. By varying the position of the locator pins,the preload of the springs, the number of springs and/or the springconstant of the springs, the forces biasing the base and the extensiontoward the deployed position are variable. In a preferred embodiment,eight springs are used to bias the base 14, and three springs are usedin the knuckle 28 between the base and the extension 18. In thisarrangement the knuckle 28 opens relatively quickly, thus accommodatingthe weight of the axle, cover, and motor 30, and allowing the motor toswing from either its fully covered or uncovered place and clear the toprail 38 or 60.

FIGS. 5 and 6 show interlocking sections 70 and 72 that may be used toform the walls 34 and 41 of the trailer. The sections 70 and 72 aregenerally identical, and of course two or more may be needed to form theextent of a trailer wall, depending upon the length of the sections andthe length of the wall required. The sections 70 and 72 havesubstantially smooth inner and outer sides joined by cross ribs 74. Eachwall section includes a male end 76 and a female end 78. The male end 76of one wall section is adapted to interlock with the female end 78 of anadjacent wall section. In a preferred embodiment, the male ends 76include a central recess 80 flanked by protrusions 82 and 84. Theprotrusions 82 and 84 in turn define respective lateral recesses 86 and88 generally proximate the outer surfaces of the wall sections. Thefemale ends 78 include a central protrusion 90 flanked by lateralprotrusions 92 and 94 generally proximate the outer surfaces of the wallsections. The central protrusion 90 and the lateral protrusions 92 and94 in turn define respective recesses 96 and 98.

When brought together, the lateral protrusions 92 and 94 lockinglyengage the lateral recesses 86 and 88, respectively. At the same time,the protrusions 82 and 84 lockingly engage the recesses 96 and 98, whilethe central protrusion 90 fits within the central recess 80. Thesections 70 and 72 are preferably extruded from aluminum. After the wallsections are preassembled, with or without the top rails, the entirepreassembly may be joined, such as by welding, to the metal rails of thetruck bed. Because the individual wall sections do not need to be weldedtogether, substantial time and effort may be avoided.

Referring again to FIG. 2, an elastic cord may be provided proximate therear of the trailer for biasing the reel 32 toward the driver's side 41of the trailer. More preferably, a cover return unit 100 is provided.The cover return unit 100 is preferably mounted on the driver's side 41of the trailer, at or near the rear of the trailer. As shown in FIG. 7,the cover return unit 100 preferably includes two halves 102 and 104molded in an automotive grade plastic and rotatably mounted on anexternal pivot pin assembly 106, and a large coil spring 108 containedinside the halves 102 and 104. The pivot pin assembly 106 is secured issecured to the trailer, preferably by bolts extending through holes 110.One end 112 of the spring 108 is secured in a groove 114 in the pivotpin assembly 106, and another end 116 of the spring 108 is secured, suchas by insertion in a groove 118, to the cover return half 102.

A sufficient length of nylon rope or cord 119, shown in FIGS. 2 and 3,is wrapped around the assembled cover return unit 100, with one endattached to the unit itself such as by a cable clamp (not shown) securedby one of the screws (not shown) extending through holes 120. The otherend of the rope 119 extends through a hole in an end cap secured on theback end of the tarp axle 32 such as by screws 122. The rope 119 ispreferably knotted at this end to prevent it from being withdrawnthrough the hole in the end cap of the reel. As the tarp reel 32 rollstoward the passenger side 34 of the trailer, i.e. uncovering thetrailer, the rope 119 unspools from the cover return unit 100. As therope unspools, it rotates the unit 100 to wind the spring 108 and storerotational torque. When the tarp 12 is returned to the driver's side 41of the trailer, the cover return unit 100 pulls on the back of the axle32 using the torque stored in the spring 108.

It should be understood that while the forms of the invention shown anddescribed above constitute preferred embodiments of the invention, theyare not intended to illustrate all possible forms thereof. The wordsused are words of description rather than limitation, and variouschanges may be made without departing from the spirit and scope of theinvention disclosed.

1. A rail for a top of a wall of a trailer, the rail comprising: a bodyadapted to engage the top of the wall, the body having a concave surfaceadapted to receive a cover reel.
 2. The rail of claim 1 wherein theconcave surface faces away from the trailer.
 3. The rail of claim 1further comprising at least one leg connected to the body.
 4. The railof claim 3 wherein the at least one leg is adapted to engage the top ofthe wall.
 5. The rail of claim 3 wherein the at least one leg is adaptedto be welded to the top of the wall.
 6. The rail of claim 1 wherein thebody comprises a plurality of ribs.
 7. The rail of claim 1 wherein thebody includes an opening adapted to anchor a cover.
 8. The rail of claim1 wherein the body extends at least a majority of a length of the wallof the trailer.
 9. The rail of claim 1 wherein the body comprisesaluminum.
 10. The rail of claim 1 wherein the body comprises a polymer.11. The rail of claim 1 wherein the body is extruded.
 12. An apparatusfor extending and retracting a cover over a trailer, the apparatuscomprising: a base pivotably connected to the trailer; an extensionconnected to the cover and pivotably connected to the base; and a railfor a top of a wall of the trailer, the rail including a body adapted toengage the top of the wall, the body having a concave surface adapted toreceive a cover reel.
 13. The apparatus of claim 12 wherein the concavesurface faces away from the trailer.
 14. The apparatus of claim 12further comprising at least one leg connected to the body.
 15. Theapparatus of claim 14 wherein the at least one leg is adapted to engagethe top of the wall.
 16. The apparatus of claim 14 wherein the at leastone leg is adapted to be welded to the top of the wall.
 17. Theapparatus of claim 12 wherein the body comprises a plurality of ribs.18. The apparatus of claim 12 wherein the body includes an openingadapted to anchor the cover.
 19. The apparatus of claim 12 wherein thebody extends at least a majority of a length of the wall of the trailer.20. The apparatus of claim 12 wherein the body comprises aluminum. 21.The apparatus of claim 12 wherein the body comprises a polymer.
 22. Theapparatus of claim 12 wherein the body is extruded.
 23. An apparatus forextending and retracting a cover over a trailer, the apparatuscomprising: a base pivotably connected to the trailer; an extensionconnected to the cover and pivotably connected to the base; a reelconnected to the extension; a motor mounted on the extension anddrivingly engaged with the reel to selectively extend and retract thecover over the trailer; and a rail for a top of a wall of the trailer,the rail including a body adapted to engage the top of the wall, thebody having a concave surface adapted to receive the reel.
 24. Theapparatus of claim 23 wherein the concave surface faces away from thetrailer.
 25. The apparatus of claim 23 further comprising at least oneleg connected to the body.
 26. The apparatus of claim 25 wherein the atleast one leg is adapted to engage the top of the wall.
 27. Theapparatus of claim 25 wherein the at least one leg is adapted to bewelded to the top of the wall.
 28. The apparatus of claim 23 wherein thebody comprises a plurality of ribs.
 29. The apparatus of claim 23wherein the body includes an opening adapted to anchor the cover. 30.The apparatus of claim 23 wherein the body extends at least a majorityof a length of the wall of the trailer.
 31. The apparatus of claim 23wherein the body comprises aluminum.
 32. The apparatus of claim 23wherein the body comprises a polymer.
 33. The apparatus of claim 23wherein the body is extruded.